Sunstreaker is so traumatized, he's reliving a conversation he had in the past. In the present, Ironhide is speaking to him. His answers/parts of the conversation fit into both perfectly.

It's a haunting scene, partly because I believe both answers apply equally to both disturbing conversations, and partly because you see how broken he still is. Combined with Ratchet immediately asking him to relive his trauma after he's been fixed earlier on... Sunstreaker got hit from every side. Every side. It's so unfair what happened to him.